Physical Sciences and Mathematics Commons^™

A Two Micron All Sky Survey View Of The Sagittarius Dwarf Galaxy. Ii. Swope Telescope Spectroscopy Of M Giant Stars In The Dynamically Cold Sagittarius Tidal Stream, Sr Majewski, We Kunkel, Dr Law, Rj Patterson, Aa Polak, Hj Rocha-Pinto, Jd Crane, Pm Frinchaboy, Cb Hummels, Kv Johnston, J Rhee, Mf Skrutskie, M Weinberg

Astronomy Department Faculty Publication Series

We have obtained moderate resolution (~6 km s-1) spectroscopy of several hundred M giant candidates selected from Two Micron All Sky Survey photometry. Radial velocities are presented for stars mainly in the southern Galactic hemisphere, and the primary targets have Galactic positions consistent with association to the tidal tail system of the Sagittarius (Sgr) dwarf galaxy. M giant stars selected from the apparent trailing debris arm of Sgr have velocities showing a clear trend with orbital longitude, as expected from models of the orbit and destruction of Sgr. A minimum 8 kpc width of the trailing stream about the Sgr …